气候变化领域集成服务门户(CCPortal): A 70-yr record of oxygen-18 variability in an ice core from the Tanggula Mountains, central Tibetan Plateau

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DOI	10.5194/cp-6-219-2010
	A 70-yr record of oxygen-18 variability in an ice core from the Tanggula Mountains, central Tibetan Plateau
	Joswiak, D. R.; Yao, T.; Wu, G.; Xu, B.; Zheng, W.
通讯作者	Joswiak, DR (通讯作者)
发表日期	2010
ISSN	1814-9324
EISSN	1814-9332
起始页码	219
结束页码	227
卷号	6 期号:2
英文摘要	A 33 m ice core was retrieved from the Tanggula Mts, central Tibetan Plateau at 5743 m a.s.l. in August 2005. Annual average delta O-18 values were determined for the upper 17 m depth (14.6 m w.eq.), representing the time series since the mid-1930s. Data are compared to previous results of an ice core from Mt. Geladaindong, 100 km to the northwest, for the period 1935-2003. During the time 1935-1960, delta O-18 values differed by 2-3 parts per thousand between the two ice cores, with generally lower ratios preserved in the Tanggula 2005 core. Differences in interannual variability and overall average ratios between the two study locations highlight the spatially variable climate controls on ice core isotope ratios within the boundary of monsoon- and westerly-impacted regions of the central Tibetan Plateau. Average annual net accumulation was 261 mm w.eq. for the period 1935-2004. The overall average delta O-18 value was -13.2 parts per thousand and exhibited a statistically significant increase from the 1935-1969 average (-13.7 parts per thousand) to the 1970-2004 average (-12.6 parts per thousand). Despite the observed increase in isotope ratios, isotopic temperature dependence was not evident, based on comparison with long-term data from meteorological stations to the north and southwest of the study location. Lack of correlation between average delta O-18 values and temperature is likely due to monsoon influence, which results in relatively greater isotopic depletion of moisture during the warm season. Evidence of monsoon impacts on precipitation in the central Tibetan Plateau has been previously documented, and statistically significant negative correlation (r=-0.37, p < 0.01) between the annual average ice core delta O-18 values and North India monsoon rainfall was observed for the period 1935-2004. Although the delta O-18 data agree well with the monsoon rainfall amount, no significant correlation was observed between the core accumulation and the monsoon rainfall amount. Previous model and observational results suggest monsoon impact on delta O-18 in precipitation may extend beyond the immediate extent of heavy monsoon rainfall, reaching the central Tibetan Plateau. These results provide evidence that the delta O-18 variability at this study location may be sensitive to southern monsoon intensity.
关键词	DONGKEMADI GLACIER AIR-TEMPERATURE MASS-BALANCE PRECIPITATION DELTA-O-18 MONSOON NORTH SOUTH REGION
语种	英语
WOS研究方向	Geology ; Meteorology & Atmospheric Sciences
WOS类目	Geosciences, Multidisciplinary ; Meteorology & Atmospheric Sciences
WOS记录号	WOS:000277185200007
来源期刊	CLIMATE OF THE PAST
来源机构	中国科学院青藏高原研究所
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/257718
推荐引用方式 GB/T 7714	Joswiak, D. R.,Yao, T.,Wu, G.,et al. A 70-yr record of oxygen-18 variability in an ice core from the Tanggula Mountains, central Tibetan Plateau[J]. 中国科学院青藏高原研究所,2010,6(2).
APA	Joswiak, D. R.,Yao, T.,Wu, G.,Xu, B.,&Zheng, W..(2010).A 70-yr record of oxygen-18 variability in an ice core from the Tanggula Mountains, central Tibetan Plateau.CLIMATE OF THE PAST,6(2).
MLA	Joswiak, D. R.,et al."A 70-yr record of oxygen-18 variability in an ice core from the Tanggula Mountains, central Tibetan Plateau".CLIMATE OF THE PAST 6.2(2010).